I have 50 forests to sample, their size range from 5 to 500 hectare. I am primarily interested in tree diversity, tree biomass, basal area etc. I will use 10 m radius plots for these variables.
I am wondering about number of plots to be sampled (Number of plots for each forest).
One approach is to use 0.5% or 1% % sampling intensity and determine the number of number of plots. What could be another practical approach of determining the number of plots for each forest? (please do not suggest methods for two stage sampling, as my resource doesn't allow that). Thank you for your kind cooperation.
You have to know at least a little about your forest samples.
The text sent by Hamit Can uses a sort of "two stage" sampling" since you have to input "Estimated standard deviation of biomass stock".
You need to know some about the variability of your forest samples in order to "Estimate" your minimum sample size.
You can always check if your sample is enough at the end of the process.
So, maybe will you end up with samples good enough (or maybe a surplus) for some of your Forest samples while others not.
Hi dear,
I think that the priliminar knowledge of those forest is very important to determine the number of plots per forest. Is there any environmental gradient acting on those forest (ex. altitude, topography, soil...) so that you could standardize the number of plots per forest and per environmental range (in terms of considered gradient)?
Dear Legrand,
Yes, this information is important. All the forests have similar environmental condition. I will not sample along env gradient but plots will be placed random.
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